Prop device for mining and tunnel construction

ABSTRACT

To temporarily secure pit and tunnel construction a prop device  1  is intended which consists of an inner pipe  2  and an out pipe  3  which can be moved while inserted in each other. The pulling apart motion is initiated when a liquid is filled into a filler opening  11  into the outer pipe  3  whose cavity  9, 2  is separated form the cavity  9  by a plate  10 . This plate  10  features a weak point  18 . Endangerment of the workers is therefore eliminated. After the extension of the inner pipe  2  from the outer pipe  3  the partial wedges  40, 41, 42  are pushed into the remaining narrow gap  45  so that the desired locking effect takes immediately place. The water or liquid can exit again from the cavity  9, 2  via the filler opening  11 . A very light prop device  1  that absorbs sufficient straining forces has been created.

DESCRIPTION

[0001] The invention concerns a prop device for underground mining and tunnel construction with an inner and outer pipe which can be pushed into each other and which can be linked via wedges and which are closed on the free ends with a footer or header plate while the cavities of the inner pipe and the outer pipe are separated by a plate and a filler opening is intended in the outer pipe.

[0002] In underground mining but also in tunnel construction, wooden support systems are still being used in spite of the commonly used hydraulic props. Thus, such areas are secured through wooden props that need only be kept open for a limited time or which shall only support partial areas. As far as possible, such wooden props are also replaced by supporting props that can be filled with building material. Such a prop device is known from the DE-PS 43 38 830. Here, the two parts, meaning the inner prop and the outer prop are being extended by filling it with building material and bracing it between the hanging and the laying part. A similar solution is also known from the DE-PS 195 14 137 whereas first of all building material is poured into one of the constructed cavities until it pushes the inner prop against the rock. Both of the prop parts are then supported against each other via wedges upon which the inner prop is also filled with building material in order to increase the supporting force and to avoid an overstraining. With those known prop devices it is disadvantageous especially that the positioning pressure through the filling of building material can only be achieved with a high expenditure of energy if at all. Alas, many times it will happen that the positioning work is already stopped with insufficient positioning force, so that first of all the rock has to settle before the prop can apply its full supporting force. Disadvantageous is also the relative extensive construction of such props or of the supporting prop device and the necessity to apply a valve to the outer pipe as well as the inner pipe because the building material that is inserted in liquid form can otherwise leak or flow out and is then not longer able to support the positioning force or the straining pressure.

[0003] The invention has the task to create a support device, preferably props, which can take over the functionality of the lost wooden prop but can be placed with positioning pressure.

[0004] The task is solved according to the invention by the fact that the filler opening features the form of only a spout and that the wedges are positioned in a narrow opening between a cylindrical expansion which forms the head of the outer pipe and the inner pipe and that they are held in their position by a place holder.

[0005] This construction of a prop device first of all has the advantage that relatively light pipes can be used which practically make up the entire prop. The only necessary filler opening does not require a valve since the water that was filled into the pipe or other utilized material is only required to extend the inner prop and thus to apply the necessary positioning pressure. Once the prop is positioned, the water or other material can be released again because it is no longer necessary for the functionality of the prop. The two prop parts, meaning the inner and the outer prop are linked with each other via the wedge in such a way that the inner prop can no longer retract into the outer prop so that the pressure that was previously created is preserved in order to completely meet the requirements of the prop function. The place holder ensures that after the extension of the inner prop out of the outer prop or the inner pipe from the outer pipe both will immediately be braced against each other and locked into each other so that the positioning pressure will remain constant. The prop itself will remain in place until the pressure from the strain onto the prop exceeds a specified value so that the prop device looses its function which for example is the case when the hydraulic prop is taken out of a strut as well as the transfer devices so that the cavity can cave in. The costs of such a prop device range within parameters that are comparable with the wooden prop, therefore significantly below those of a hydraulic prop and those of a building material prop. Advantageous is foremost the simple design, because it can be set up with simple tools, meaning also a simple filler pistol can be used to extend both parts of the prop device and to therefore position them. You can fall back on existing devices which also have the advantage that no high pressure is necessary and neither are special materials, but moreover, regular tap water which is available underground can be used.

[0006] According to a useful design it is intended that the spout is fitted with a brace that fixates the pistol that sets the water pressure during the filling process. Thus it shall be avoided that the water pressure pistol falls down due to carelessness and that water can possibly overflow. Most of all, the water pressure pistol at the same time functions as a seal of the spout so that with the unintended removal of the water pressure pistol the water that has already been filled into the prop would exit freely.

[0007] An additional useful design intends that the outer and inner pipes are designed to allow a continuously variable extension of 300-500 mm. With 300-500 mm the required positioning pressure can normally be reached. With that it is assumed that the total length measures such that the intended distance between the hanging and the laying part of the track can be achieved.

[0008] Previously in the text it has been referred to the fact that the positioning of the props is achieved by bracing it between the upper and the lower limits of the track whereas the inner pipe is extended coming out of the outer pipe. To make this possible, the outer pipe and the inner pipe are separated by a plate. The extension takes place in an especially safe manner when the plate corresponds with the inner pipe and features a weak point which bursts when the allowed filling pressure in the outer pipe is exceeded. The inner pipe practically features a bottom which however features a special characteristic in that it is destroyed when the filling pressure is exceeded so that the water or other medium that has been filled into the cavity of the outer pipe under too much pressure can flow into the cavity of the inner pipe in order to release excess pressure. Thus, damage, but especially an endangerment of the workers can be avoided because excess pressure and the explosion of the wall of for example the outer pipe cannot happen even when by mistake too much water pressure is used. Such a prop device is therefore especially user friendly and safe.

[0009] The previously described weak point can be implemented in an especially useful way when the plate is made out of rubber or compatible work material and when it features a weak point in the middle where the material is thinner and which facilitates as a weak point. Such a plate can be easily mounted and designed that it bursts exactly at a specified pressure value, and it is here intended to let the weak point break at +100 bar, so that the pressure is then released. It is thinkable, for example, that the material is thinner exactly in the center point of the plate so that at the breaking point the water can access the cavity in the center.

[0010] An especially inexpensive solution for such a prop device can be achieved when the outer pipe and the footer plate are linked with each other via a welded seam whereas the head plate is attached to the inner pipe on several, preferably three fixating points. The welding sprocket which fixates the footer plate seals it sufficiently to extend the inner pipe out of the outer pipe during the positioning process. Even if water or other media remain in the outer pipe, it can exit through the welding sprocket after some time if it doesn't seal tight enough over time. This is absolutely not dangerous, because the prop has then been set. In the area of the header plate it only has to be guaranteed that the header plate does not detach from the inner pipe whereas it is sufficient that it is attached on three fixating points.

[0011] The effective coupling of inner and outer pipe through the wedge or wedges can be achieved according to the invention by the fact that the head of the outer pipe features a slope on the side facing the inner pipe which corresponds with the wedges whereas the sides of the wedge and the inner pipe that connect with each other run vertical and parallel towards each other. Since this wedge is held from above through the place holder, the wedge will first slightly be moved with the inner and the outer pipe so that it cannot have a braking effect in order to effectively prevent the retraction of the inner pipe when the movement stops and especially during the bracing between the upper and lower limits of the track. Thus effect is especially facilitated by the fact that the sides that face the inner pipe run vertical to each other while the sides on the other side feature a corresponding wedge slope.

[0012] This ‘automated bracing’ of the wedge or the wedges is also being facilitated by the fact that between the upper edge of the wedges and the bottom of the header plate a cylinder spring is positioned which acts as a place holder. This cylinder spring ensures that the wedges can only be pushed out of their active position in a limited fashion in order to be pushed into their bracing position immediately upon completion of the extension process. Therefore, the locking effect is immediately effective when the extension of the pipes has been finished.

[0013] The bracing of the wedge or the wedges via the place holder or the cylinder spring is being facilitated by the fact that the upper end of the sides of the wedges and/or the outer wall of the inner pipe is equipped with a saw tooth thread. The saw tooth thread for once prevents that the wedges move too far out of their position during the extension of the pipes and facilitates the bracing when the locking effect takes place.

[0014] In order to utilize sufficiently effective wedges, the invention intends that the head of the outer pipe is shaped as a bucket and is connected via a weld with the upper end piece of the outer pipe. Thus, wedges that correspond in size with or are fitted with the diameter of the head can be utilized and whose slope is sufficient to create the necessary locking effect with the necessary safety on a short distance.

[0015] As soon as the pipes, meaning the inner and the outer pipe, are pulled apart the header plate moves away from the bucket-like head of the outer pipe and therefore from the cylinder spring or the place holder. Nevertheless, the cylinder spring is kept in an active position due to the fact that a middle piece is positioned between cylinder spring and the bottom of the header plate which acts as a spring lock and is connected with the head of the outer pipe via a piece of wire which can be detached. This middle piece ensures that after the header plate is removed from the head of the outer pipe the spring is nevertheless under tension and that thus the wedge or the wedges can be held in the active position. The middle piece is effectively attached via the wire, whereas the wire is easy to install which presents advantages with this inexpensive design of the prop device.

[0016] An effective tight positioning between upper and lower limits of the track is being facilitated by the fact that the header plate as well as the footer plate feature cams which extend over the outer surface. Those cams can penetrate the upper and lower limits of the track to add to the effectiveness of the prop device. This is also advantageous because it allows for the option to first pull or push the pipes apart by hand in order to then contribute to the effort with the water filling. Due to the specially shaped wedges and their strain through the cylinder spring it is always ensured that with the manual extension the retraction of the inner pipe into the outer pipe is prevented.

[0017] The effectiveness of the wedge regarding the locking effect is being facilitated if the wedge consists of three partial wedges which are held in place and positioned in a distance to each other by a holding wire. Thus the wedges can be pushed from the ‘resting position’ into the ‘locking position’ without interfering with each other and without any hindrance or the danger that they might jam against each other. For this they are fixated in a distance to each other.

[0018] The optimal distance between the partial wedges is ensured according to the invention due to the fact that the partial wedges are held in a distance to each other by a holding wire which features indentations that pre-determine the distance. Thus the partial wedges can neither move when the pipes are extended nor when they are retracted from the pre-determined position. Moreover it is ensured that they settle exactly in the intended narrow gap and then initiate the locking effect.

[0019] The invention is distinguished due to the fact that a prop device has been created that can be manufactured with relative low cost for the value and which can be positioned well and positioned safely. Therefore such a prop is well suited for use in mine or pit construction which shall be dropped or also which shall be additionally secured with such a prop device. For the locking effect of the two within each other adjustable pipes three partial wedges of a ring wedge are used effectively whereas one partial piece of the ring wedge is not utilized and whereas those three partial wedges are positioned and manufactured exactly so that with the finalization of the extension process the wedges or partial wedges are pushed into their locking position and position themselves there tightly. This insertion can if necessary also be initiated via a cylinder spring which is moved based on contact and which is going to always want to push the wedges into their active position. It is moreover especially advantageous that a safety feature is in place which ensures that even during the filling process with a medium that is filled in under too much pressure there won't be any damages. Instead, at most, a plate between the cavities will be destroyed so that the collected pressurized water can be released into the cavity of the inner pipe so that dangerous conditions cannot occur.

[0020] Additional details and advantages of the invented object can be found in the following description of the corresponding drawings where a preferred design example is depicted with the necessary details and individual parts.

[0021] It is shown in:

[0022]FIG. 1 a side view of the prop device, partially in a section,

[0023]FIG. 2 a partial view of the transition area between outer and inner pipe in a section,

[0024]FIG. 3 a section through inner pipe and outer pipe in the area of the filler opening and

[0025]FIG. 4 a longitudinal section in the area of the wedges.

[0026]FIG. 1 shows a prop device 1 in the shape of a prop which consists of an inner pipe 2 and an outer pipe 3 whereas the inner pipe 2 is depicted in a sectional while being inserted. On the left side the inner pipe 2 is mostly extended out of the inner pipe 3. On the free end 4 of the inner pipe 2, a head plate 5 is intended as well as a footer plate 7 on the free end 6 of the outer pipe 3. This head plate 5 and the footer plate 7 feature cams 38 or 39 on the outer surface 37 which shall facilitate and ensure the fixation on the rock meaning between the hanging and the laying part of the track.

[0027] In the upper part of the outer pipe 3, a wedge 8 is positioned in such a fashion that it locks the inner pipe 2 and the outer pipe 3 in the depicted example in such a way that the inner pipe 2 can no longer retract into the outer pipe 3. Additional details in this matter further along in the document.

[0028] The cavities 9, 1 or 9, 2 are separated from each other by a plate 10 so that via the filler opening 11 water or another medium can be filled into the cavity 9, 2 in order to push the inner pipe 2 out of the outer pipe 3. The shape of the plate 10 facilitates this outward movement of the inner pipe 2 out of the outer pipe 3. It is visible in FIG. 1 as well as in FIG. 3 that this filler opening 11 in fact is just a spout 12 in which a filler spout can be inserted. This filler spout, which is not depicted here, is held in position by a brace 16 in order to avoid the unintended overspill of the inserted medium, meaning most of all water.

[0029] The cavity 9, 2 is created for once by the plate 10 and also by the footer plate 7 as well as the outer pipe 3. At the same time, the fixation of the footer plate 7 that is depicted in FIG. 1 reaches over the welded seam 19. The welded seam 19 guarantees a sufficient seal in order to ensure the extension of the inner pipe and the outer pipe 2, 3.

[0030]FIG. 3 shows the plate 10 complementary whereas here a plate 10 is shown that is made of rubber. It features a weak point 18 in the middle which ensures that no excess pressure can build up in the cavity 9, 2 when the water is filled in via the filler opening 11 or the spout 12. If the pre-determined pressure of for example 100 bar be exceeded, this plate 10 would burst in the area of the weak point 18 and the inserted water is released into the cavity 9,2 to release the pressure.

[0031]FIG. 2 clarifies first of all that in contrast with the footer plate 7 in relation to the fixation of the header plate 5 onto the inner pipe 2 only a few fixation points 20 are necessary. of those fixation points, for example 3 are sufficient, in order to avoid that the header plate 5 falls off the inner pipe 2.

[0032] It can also be seen on FIG. 2 that between the bottom of the header plate 5 and the upper edge 26 of the wedge 8 a place holder 15 is intended, here in the form of a cylinder spring 28. This cylinder spring 28 ensures that the wedge 8 always sits in the ‘attention-position’ as shown on FIG. 2 and it also ensures that with the insertion of the inner pipe 2 those movement is immediately blocked through the wedge 8. For this the wedge 8 and the head 14 that builds the upper edge of the outer pipe 3 feature corresponding slopes whereas the side 21 that faces the inner pipe 2 features vertical or close to vertical sides of the wedge 8 or 24 of the inner pipe 2. The head 14 that achieves this wedge effect is, like it is visible, positioned onto the upper end piece 33 of the outer pipe 3 and fixated via the weld 32. This weld 32 can consist of partial welds meaning it doesn't necessarily have to run around continuously, because it is not necessary to seal this area.

[0033] In the area of the upper end 29 of the sides 23, 24 a saw tooth thread is placed. This increases the friction and ensures that both parts lock into each other and after achieving the wedge effect cannot free themselves again. This of course is also prevented through the cylinder spring 28.

[0034] After the extension of the inner pipe 2 out of the outer pipe 3, the support of the cylinder spring 28 would no longer be possible. For this reason, a middle piece 35 is intended that is placed in this area and which is fixated with a wire 36. This middle piece serves as a counter bearing of the cylinder spring 28.

[0035] Finally, FIG. 4 shows a section of the wedge 8. You can see that this wedge 8 consists of three partial wedges 40, 41, 42 whereas those are fixated via a holding wire 43 and thus through the indentations 44.1, 44.2, and 44.3. The holding wire 43 which is also indicated in FIG. 2, quasi connects the individual partial wedges 40, 41, 42 with each other and ensures that they are always in the pre-determined and optimal position.

[0036] During the extension process of the inner pipe 2 and the outer pipe 3 the partial wedges 40, 41, 42 are pushed upwards with the inner pipe 2 whereas this is also facilitated through the saw tooth thread 31. Thus it is possible without any problems that through the filling of a liquid into the cavity 9, 2 of the outer pipe 3 the inner pipe 2 is being pushed out. The cylinder spring 28 then prevents a complete pushing out of the wedge 8 or of the partial wedges 40, 41, 42 so that those will always remain in the ‘pay-attention-position’. When the inner pipe 2 has reached its final position, the partial wedges 40, 41, 42 slide into the corresponding narrow gap 45 between head 14 and inner pipe 2 so that the desired locking effect is achieved. The inner pipe 2 can no longer retract into the outer pipe. The desired positioning pressure is achieved and the security of the corresponding room is ensured.

[0037] All listed characteristics which are also depicted on the drawings, individually or in combination with each other are being considered essential for the invention. 

1. a prop device for underground mining and tunnel construction with an inner and outer pipe (2, 3) which can be pushed into each other and which can be linked via wedges (8) and which are closed on the free ends (4, 6) with a footer (7) or header plate (5) while the cavities (9) of the inner pipe (2) and the outer pipe (3) are separated by a plate (10) and a filler opening (11) is intended in the outer pipe (3), characterized by the fact that the filler opening (11) features the form of only a spout (12) and that the wedges (8) are positioned in a narrow opening (45) between a cylindrical expansion which forms the head (14) of the outer pipe and the inner pipe and that they are held by a place holder in their position:
 2. Prop device according to claim 1, characterized by the fact that the spout (12) is fitted with a brace (16) that fixates the pistol that sets the water pressure during the filling process.
 3. Prop device according to one of the previous claims, characterized by the fact that the outer and inner pipes (2, 3) are designed to allow a continuously variable extension of 300-500 mm.
 4. Prop device according to one of the previous claims, characterized by the fact that the plate (10) corresponds with the inner pipe (2) and features a weak point (18) which bursts when the allowed filling pressure in the outer pipe (3) is exceeded.
 5. Prop device according to one of the previous claims, characterized by the fact that the plate (10) is made out of rubber or compatible work material and features a weak point (18) in the middle.
 6. Prop device according to claim 5, characterized by the fact that the weak point breaks at +100 bar.
 7. Prop device according to one of the previous claims, characterized by the fact that the outer pipe (3) and the footer plate (7) are linked with each other via a welded seam (19).
 8. Prop device according to one of the previous claims, characterized by the fact that the head plate (5) is attached to the inner pipe (2) on several, preferably three fixating points (20).
 9. Prop device according to one of the previous claims, characterized by the fact that the head (14) of the outer pipe (3) features a slope (22) on the side facing the inner pipe (2) which corresponds with the wedges (8) whereas the sides (23, 24) of the wedge (8) and the inner pipe (2) that connect with each other run vertical and parallel towards each other.
 10. Prop device according to one of the previous claims, characterized by the fact that between the upper edge (26) of the wedges (8) and the bottom (27) of the header plate (5) a cylinder spring (28) is positioned which acts as a place holder (15).
 11. Prop device according to one of the previous claims, characterized by the fact that the upper end (29) of the sides (23, 24) of the wedges (8) and/or the outer wall (30) of the inner pipe (2) is equipped with a saw tooth thread (31).
 12. Prop device according to one of the previous claims, characterized by the fact that the head (14) of the outer pipe (3) is shaped as a pot and is connected via a weld (32) with the upper end piece (33) of the outer pipe (3).
 13. Prop device according to claim 10, characterized by the fact that a middle piece is positioned between cylinder spring and the bottom of the header plate which acts as a spring lock and is connected with the head of the outer pipe via a piece of wire which can be detached.
 14. Prop device according to one of the previous claims, characterized by the fact that the header plate (5) as well as the footer plate (7) feature cams (38, 39) which extend over the outer surface (37).
 15. Prop device according to one of the previous claims, characterized by the fact that the wedge (8) consists of three partial wedges (40, 41, 42) which are held in place and positioned in a distance to each other by a holding wire (43).
 16. Prop device according to one of the previous claims, characterized by the fact that the partial wedges (40, 42, 42) are held in a distance to each other by a holding wire (43) which features indentations (44) that pre-determine the distance. 